$OpenBSD: patch-src_mutex_cpp,v 1.1 2017/04/30 08:56:45 espie Exp $
--- src/mutex.cpp.orig
+++ src/mutex.cpp
@@ -24,6 +24,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, 
 #include "error.h"
 #include <SDL.h>
 
+namespace dd {
 mutex::mutex()
 {
 	mtx = SDL_CreateMutex();
@@ -52,4 +53,5 @@ void mutex::unlock()
 {
 	if (SDL_mutexV(mtx) < 0)
 		throw sdl_error("mutex unlock failed");
+}
 }
